Maybe not, but Gruden did some things in his own right to that team that did win the Super Bowl. And Dungy had a lot of help putting the team together. Keep in mind that a large part of Tampa's defense, the strength of that team, was already in place before Dungy got there. So he rode on some coat tails a little himself in that regard.
Dungy still had 5 starters on defense in his 2nd year that were there before. They didn't have a lot of talent, the 4 years before Dungy got there they were 7-9, 6-10, 6-10 and 5-11. Gruden had 9 starters on defense from Dungy in his Super bowl year.